Add Extra Repositories

Software packages and programs are freely available for download at multiple online sites with standardized structures, called repositories. There are repositories officially sanctioned and monitored by the Kubuntu/Ubuntu developer community, while other repositories are independently provided, without official sanction or supervision (and should be used with caution). Additional information is available from the Kubuntu Repository Guide.

Types of Repositories

There are four major package repository types in Kubuntu:

main - Supported and supervised by Canonical. This is the major part of the distribution.

restricted - Software not licensed under the GPL (or similar software license), but supported and supervised by Canonical.

universe - Software licensed under the GPL (or similar license) and supported by users.

multiverse - Software not licensed under the GPL (or similar license), but supported by users.

There are also these additional types of repositories:

Precise-updates - Updates to official packages.

Precise-backports - Current version software from Quantal Quetzal (Precise+1) that has been backported to Precise Pangolin.

Precise-proposed - Proposed updates & changes (bleeding edge stuff).

Third party repositories

Software developers often maintain their own repositories, from which software packages can be downloaded and installed directly to your computer (if you add the repository to your list). Many of these third party repositories and software packages have never been reviewed by the (K)Ubuntu/Debian community and can present a security risk to your computer. Trojans, backdoors, and other malicious software can be present at any unregulated repository. When using repositories not endorsed by the (K)ubuntu/Debian community, make sure you have utter confidence in that site before enabling the repository and installing a software package from it.

PPA repositories

A Personal Package Archive (PPA) is a special software repository used for experimental source packages still under development. Such software has not been approved by the Debian or Ubuntu developers (but may eventually become an accepted package). Use this software at your own risk just like any other third party repository software.

Note: If add-apt-repository is not available on your system, then install it with the package:

sudo apt-get install python-software-properties

Edit the repository sources list

This is an optional, labor intensive method. Do this at your own risk. Modify the default Kubuntu sources.list only if you understand what you're doing. Mixing repositories can break your system. For more information see the Ubuntu Command-line Repository guide.

Note: wget - retrieves a file from a network location. --quiet = no output. -O - = Output downloaded item to the screen. The | (pipe symbol) is used to capture the output from the previous command and use it as an input for the piped command (i.e. apt-key, which adds it to the keyring).

Alternatively (and perhaps more easily), you can use apt-key directly:

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys KEY

where KEY is the missing key code printed in apt-get output, e.g. EF4186FE247510BE.